For those who have never made offerings, here are a few key things:
Research the being you want to work with.
If you are evoking a King of Hell or similar rank, you need to provide a libation. A libation is a tribute that usually is a drink of some kind. Kings I believe also have the correspondence of gold as the metal but don’t quote me on that perhaps that’s not every spirit.
Trust yourself. Only give what you feel like is appropriate, but also remember that the spirit will likely tell you what you need to give them. Example if you have two gold rings, and you give them one but feel like you must give two, then do so.